Seconds CountDown Timer

Question

I have a lblCountdown with an int value of 60. I want to make the int value of the lblCountDown decrease with seconds until it reaches 0.

This is what I have so far:

Answer 1

int segundo = 0;
DateTime dt = new DateTime();

private void timer1_Tick(object sender, EventArgs e){
    segundo++;
    label1.Text = dt.AddSeconds(segundo).ToString("HH:mm:ss");
}